WASHINGTON -LRB- CNN -RRB- -- Isaac Lidsky arrives in front of the U.S. Supreme Court , stops suddenly and , upon hearing a voice , extends his hand in greeting almost instinctively .

Isaac Lidsky graduated from Harvard University at 19 . Retinitis pigmentosa has seriously impaired his vision .

Seemingly simple gestures such as a hello do n't always come easily for a man who is legally blind .

But this has n't deterred the ex-Justice Department prosecutor from pursuing a promising legal career , one that will take him inside the nation 's highest court in a few weeks .

The Florida native will join 36 of the nation 's top young attorneys as law clerks to Supreme Court justices for the 2008 - '09 term . He will be the first legally blind law clerk in the court 's history .

Lidsky , 28 , will work with the retired Justice Sandra Day O'Connor and will be assured of long days writing and researching cases .

`` I certainly am nervous to the extent I am eager to be helpful to the justice and productive , '' he said . `` I just want to do good work . '' Watch as the lawyer will break new ground at the court ''

Lidsky , a one-time actor , may be vaguely familiar to adults of a certain age . He played the lovable geek Barton `` Weasel '' Wyzell on the NBC series `` Saved by the Bell : The New Class '' in the 1990s .

`` There 's a little bit of a cringe factor because my character was not necessarily the coolest kid in school , but certainly , -LSB- there 's -RSB- fond memories , '' he recalled . `` It was an incredible experience for a kid to have . ''

Around that time , the 13-year-old was diagnosed with retinitis pigmentosa , a degenerative eye disease that already had struck two of his older sisters . The symptoms were slow to develop , so Lidsky came to terms early with the idea of losing his vision . Now his sight is seriously impaired .

Lidsky said his parents , Betti and Carlos Lidsky , did not allow self-pity and encouraged him to help others like himself .

`` Right away my parents really led the charge on saying , ` How can we take this challenge and turn it into something positive ? ' '' he said . `` So for 15 years we have been doing just that . ''

Acting was never going to be a career for Lidsky . It was the law that always attracted him . As a child he went to court with his father , a prominent Miami lawyer . Becoming a Supreme Court law clerk , he said , was a lifelong dream .

After graduating at 19 from Harvard University , he earned a degree from its law school , with a brief stop in between as an Internet business entrepreneur .

In 2004 , he began a clerkship with Judge Thomas Ambro of the 3rd U.S. Circuit Court of Appeals , based in Philadelphia , Pennsylvania .

Ambro became a mentor to the bright young lawyer and witnessed a sudden decline in his vision .

`` You could tell things were getting worse , '' Ambro said . By the end of the one-year assignment , `` he now needed a cane and was using a guide dog . Once he had no idea I was in the same room with him until I spoke . ''

But that did not dull Lidsky 's drive to succeed .

`` He had a real good sense of what he was facing , '' Ambro said . `` He 's determined to make it in the same way as other people who succeed . For him it was simply a matter of getting the tools to do it . ''

Those tools include optical character recognition software , which scans printed words electronically and reads them back to him , and a Blackberry-type communication device that sends and receives e-mail audibly .

Friends said he was a little reluctant over the years to embrace much of the technology , as he sought to preserve his independence as long as possible .

After his clerkship came a stint in the Justice Department 's Civil Division , where he argued about a dozen cases in federal courts . He said his acting skills came in handy when pleading before often skeptical judges .

With the recommendations of Ambro and others , Lidsky applied four times to be a Supreme Court law clerk but was rejected . A meeting with longtime federal Judge David Tatel , who also is blind , convinced Lidsky he should not give up his dream .

Then came the call from O'Connor .

`` Sitting in her chambers , here I was worrying about having to recall the minutiae of legal doctrine '' for the personal interview , he recalled . `` But we fell into talking about our families and philosophies , and she made me feel very warm and welcome . ''

O'Connor was not available for an interview , but former clerks said they remember her as a nurturing type who nevertheless demands much from them .

`` I have no doubt Justice O'Connor will keep me very busy , '' Lidsky said .

In addition , Lidsky likely will be assigned to an active justice to sort through the 9,000-some appeals that reach the high court every year . In that capacity , he would recommend which cases should be accepted for review and help write early drafts of opinions .

O'Connor also will continue her practice of sitting in on several appeals court cases a year , so Lidsky will assist her on those , along with the 78-year-old 's busy schedule of teaching , speeches and public advocacy .

Lidsky will have to scale back involvement in his foundation , Hope for Vision , which he created with his wife , Dorothy , and some friends to raise awareness of blinding diseases . His group is launching a campaign this week to find a cure for blindness by 2020 .

`` We have communities of Hope across the country that do events to raise awareness and funding for research , '' he said . `` It 's purely volunteer-driven , very grass-roots . Over 98 percent of the money we raise goes directly to scientific grants . ''

As for the future , Lidsky plans to go to London , England , after his clerkship ends , so his wife can finish her master 's degree . He would be set to rejoin his law firm , where he has taken a leave of absence , but has no specific career goals .

`` In 10 or 15 years , I would bet he will be a man still on your radar screen , '' Ambro predicts .

Lidsky appears more modest .

`` I 'm not out there to set any kinds of records or prove anything to anybody , '' he said . `` As odd as it may sound , losing my vision has in a lot of ways been a very rewarding experience for me . ''

CNN 's Kelli Arena contributed to this report .

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Isaac Lidsky is set to become first legally blind law clerk at U.S. Supreme Court

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Lidsky will work with retired Justice Sandra Day O'Connor , who still hears appeals

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Lidsky played Weasel on NBC 's `` Saved by the Bell : The New Class ''

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He and wife founded Hope for Vision , a foundation that seeks a cure for blindness